The present invention relates to orthopedic instruments and more particularly to an apparatus used to evaluate the implantation of femur fixation devices inserted through a fractured neck of a femur bone.
Hip fractures are comparatively common where the femur bone is fractured in the neck or in the ball head. A great many devices have been proposed for the reduction of fractures of this type. A fracture reduction device also known as a orthopedic hop fixation device, may feature a lag screw adapted to be implanated into the ball head of the femur and extended, when in use, through the neck of the femur thereby securely fastening the ball head of the femur to the remaining trochanteric portion of the femur.
An orthopedic hip fixation device is disclosed in U.S. Pat. No. 4,438,762 to Kyle, the inventor of the present invention. U.S. Pat. No. 4,438,762 discloses the structure and use of the orthopedic hip fixation device. The U.S. Pat. No. 4,438,762 is here incorporated by reference as there fully set forth. This prior art patent does not teach a surgeon how to properly select and insert the fixation device respecting the penetration depth into the head ball of a fracture femur bone.
During surgical operations, the orthopedic hip fixation device having a lag screw at one end thereof, is implanted into the femur. The surgeon may have selected a orthopedic hip fixation device which is too large for the patient's femur in the trochanteric area. Or, during implantation, the orthopedic hip fixation device may have been implanted too far into the femur ball head. Consequently, during implantation of the orthopedic hip fixation device, the lag screw may break out of the femur ball head and penetrate into the socket area of the hip joint. During post operative rehabilitation, the patient may have the socket joint damaged by virtue of the lag screw extending into socket tissues of the hip joint. The medical surgeon may not know at time of surgery whether or not the lag screw end of an orthopedic hip fixation device has entered the hip joint area. Thus, the surgeon may not know whether or not the patient will be subjected to post operative damage to the socket tissues when selecting an orthopedic hip fixation device that is too large or when implanting the fixation device too far into the ball head area of the fractured femur bone.